A police officer is seen near a blast scene, which has been cordoned off, in downtown Urumqi, capital of northwest China's Xinjiang Uygur Autonomous Region, May 22, 2014. An unknown number of people were killed and injured after explosions occurred Thursday morning at an open market in Urumqi. Witnesses said two cross-country vehicles driving from north to south ploughed into people in the market at 7:50 a.m. Explosives were thrown out of the vehicles. One of the vehicles exploded in the market. The blast scene has been cordoned off. All injured people have been sent to hospital while investigations are underway. (Xinhua/Cao Zhiheng)